Title : Method and Apparatus for Non-Destructively Measuring Local Resistivity of Semiconductors.

Descriptive Note : Patent, Filed 17 Jun 92, patented 3 Jan 95,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Gaskill, D K ; Bottka, Nicholas ; Berry, Alok K

Report Date : 03 Jan 1995

Pagination or Media Count : 14

Abstract : An apparatus for non-destructively measuring resistivity of a semiconductor, such as InP, comprises light sources for illuminating a preselected portion of the semiconductor with first and second light beams, each of a preselected single wavelength, the first light beam operating to excite the semiconductor by photo injecting carriers, and the second light beam bombarding the local portion of the semiconductor with a preselected photon energy. The apparatus measures a fractional change in reflectance of the second light beam responsive to the first light beam, and records this fractional change in reflectance for various values of photon energy of the second light beam, to generate a photoreflectance line-shape. The photoreflectance line-shape is used to calculate a photoreflectance line-shape phase angle, which is used to determine the resistivity of the preselected portion of the semiconductor. (AN)